glibc/sysdeps/x86_64/dl-trampoline.S
H.J. Lu 2eb9ef29b6 Improve bndmov encoding with zero displacement
If x86-64 assembler doesn't support MPX, we encode bndmov instruction by
hand.  When displacement is zero, assembler generates shorter encoding.
This patch improves bndmov encoding with zero displacement so that ld.so
is identical when using assemblers with and without MPX support.

	* sysdeps/x86_64/dl-trampoline.S (_dl_runtime_resolve): Improve
	bndmov encoding with zero displacement.
2015-07-09 09:30:20 -07:00

440 lines
13 KiB
ArmAsm

/* PLT trampolines. x86-64 version.
Copyright (C) 2004-2015 Free Software Foundation, Inc.
This file is part of the GNU C Library.
The GNU C Library is free software; you can redistribute it and/or
modify it under the terms of the GNU Lesser General Public
License as published by the Free Software Foundation; either
version 2.1 of the License, or (at your option) any later version.
The GNU C Library is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
Lesser General Public License for more details.
You should have received a copy of the GNU Lesser General Public
License along with the GNU C Library; if not, see
<http://www.gnu.org/licenses/>. */
#include <config.h>
#include <sysdep.h>
#include <link-defines.h>
#if (RTLD_SAVESPACE_SSE % 32) != 0
# error RTLD_SAVESPACE_SSE must be aligned to 32 bytes
#endif
/* Area on stack to save and restore registers used for parameter
passing when calling _dl_fixup. */
#ifdef __ILP32__
/* X32 saves RCX, RDX, RSI, RDI, R8 and R9 plus RAX. */
# define REGISTER_SAVE_AREA (8 * 7)
# define REGISTER_SAVE_RAX 0
# define PRESERVE_BND_REGS_PREFIX
#else
/* X86-64 saves RCX, RDX, RSI, RDI, R8 and R9 plus RAX as well as BND0,
BND1, BND2, BND3. */
# define REGISTER_SAVE_AREA (8 * 7 + 16 * 4)
/* Align bound register save area to 16 bytes. */
# define REGISTER_SAVE_BND0 0
# define REGISTER_SAVE_BND1 (REGISTER_SAVE_BND0 + 16)
# define REGISTER_SAVE_BND2 (REGISTER_SAVE_BND1 + 16)
# define REGISTER_SAVE_BND3 (REGISTER_SAVE_BND2 + 16)
# define REGISTER_SAVE_RAX (REGISTER_SAVE_BND3 + 16)
# ifdef HAVE_MPX_SUPPORT
# define PRESERVE_BND_REGS_PREFIX bnd
# else
# define PRESERVE_BND_REGS_PREFIX .byte 0xf2
# endif
#endif
#define REGISTER_SAVE_RCX (REGISTER_SAVE_RAX + 8)
#define REGISTER_SAVE_RDX (REGISTER_SAVE_RCX + 8)
#define REGISTER_SAVE_RSI (REGISTER_SAVE_RDX + 8)
#define REGISTER_SAVE_RDI (REGISTER_SAVE_RSI + 8)
#define REGISTER_SAVE_R8 (REGISTER_SAVE_RDI + 8)
#define REGISTER_SAVE_R9 (REGISTER_SAVE_R8 + 8)
.text
.globl _dl_runtime_resolve
.type _dl_runtime_resolve, @function
.align 16
cfi_startproc
_dl_runtime_resolve:
cfi_adjust_cfa_offset(16) # Incorporate PLT
subq $REGISTER_SAVE_AREA,%rsp
cfi_adjust_cfa_offset(REGISTER_SAVE_AREA)
# Preserve registers otherwise clobbered.
movq %rax, REGISTER_SAVE_RAX(%rsp)
movq %rcx, REGISTER_SAVE_RCX(%rsp)
movq %rdx, REGISTER_SAVE_RDX(%rsp)
movq %rsi, REGISTER_SAVE_RSI(%rsp)
movq %rdi, REGISTER_SAVE_RDI(%rsp)
movq %r8, REGISTER_SAVE_R8(%rsp)
movq %r9, REGISTER_SAVE_R9(%rsp)
#ifndef __ILP32__
# We also have to preserve bound registers. These are nops if
# Intel MPX isn't available or disabled.
# ifdef HAVE_MPX_SUPPORT
bndmov %bnd0, REGISTER_SAVE_BND0(%rsp)
bndmov %bnd1, REGISTER_SAVE_BND1(%rsp)
bndmov %bnd2, REGISTER_SAVE_BND2(%rsp)
bndmov %bnd3, REGISTER_SAVE_BND3(%rsp)
# else
# if REGISTER_SAVE_BND0 == 0
.byte 0x66,0x0f,0x1b,0x04,0x24
# else
.byte 0x66,0x0f,0x1b,0x44,0x24,REGISTER_SAVE_BND0
# endif
.byte 0x66,0x0f,0x1b,0x4c,0x24,REGISTER_SAVE_BND1
.byte 0x66,0x0f,0x1b,0x54,0x24,REGISTER_SAVE_BND2
.byte 0x66,0x0f,0x1b,0x5c,0x24,REGISTER_SAVE_BND3
# endif
#endif
# Copy args pushed by PLT in register.
# %rdi: link_map, %rsi: reloc_index
movq (REGISTER_SAVE_AREA + 8)(%rsp), %rsi
movq REGISTER_SAVE_AREA(%rsp), %rdi
call _dl_fixup # Call resolver.
movq %rax, %r11 # Save return value
#ifndef __ILP32__
# Restore bound registers. These are nops if Intel MPX isn't
# avaiable or disabled.
# ifdef HAVE_MPX_SUPPORT
bndmov REGISTER_SAVE_BND3(%rsp), %bnd3
bndmov REGISTER_SAVE_BND2(%rsp), %bnd2
bndmov REGISTER_SAVE_BND1(%rsp), %bnd1
bndmov REGISTER_SAVE_BND0(%rsp), %bnd0
# else
.byte 0x66,0x0f,0x1a,0x5c,0x24,REGISTER_SAVE_BND3
.byte 0x66,0x0f,0x1a,0x54,0x24,REGISTER_SAVE_BND2
.byte 0x66,0x0f,0x1a,0x4c,0x24,REGISTER_SAVE_BND1
# if REGISTER_SAVE_BND0 == 0
.byte 0x66,0x0f,0x1a,0x04,0x24
# else
.byte 0x66,0x0f,0x1a,0x44,0x24,REGISTER_SAVE_BND0
# endif
# endif
#endif
# Get register content back.
movq REGISTER_SAVE_R9(%rsp), %r9
movq REGISTER_SAVE_R8(%rsp), %r8
movq REGISTER_SAVE_RDI(%rsp), %rdi
movq REGISTER_SAVE_RSI(%rsp), %rsi
movq REGISTER_SAVE_RDX(%rsp), %rdx
movq REGISTER_SAVE_RCX(%rsp), %rcx
movq REGISTER_SAVE_RAX(%rsp), %rax
# Adjust stack(PLT did 2 pushes)
addq $(REGISTER_SAVE_AREA + 16), %rsp
cfi_adjust_cfa_offset(-(REGISTER_SAVE_AREA + 16))
# Preserve bound registers.
PRESERVE_BND_REGS_PREFIX
jmp *%r11 # Jump to function address.
cfi_endproc
.size _dl_runtime_resolve, .-_dl_runtime_resolve
#ifndef PROF
.globl _dl_runtime_profile
.type _dl_runtime_profile, @function
.align 16
cfi_startproc
_dl_runtime_profile:
cfi_adjust_cfa_offset(16) # Incorporate PLT
/* The La_x86_64_regs data structure pointed to by the
fourth paramater must be 16-byte aligned. This must
be explicitly enforced. We have the set up a dynamically
sized stack frame. %rbx points to the top half which
has a fixed size and preserves the original stack pointer. */
subq $32, %rsp # Allocate the local storage.
cfi_adjust_cfa_offset(32)
movq %rbx, (%rsp)
cfi_rel_offset(%rbx, 0)
/* On the stack:
56(%rbx) parameter #1
48(%rbx) return address
40(%rbx) reloc index
32(%rbx) link_map
24(%rbx) La_x86_64_regs pointer
16(%rbx) framesize
8(%rbx) rax
(%rbx) rbx
*/
movq %rax, 8(%rsp)
movq %rsp, %rbx
cfi_def_cfa_register(%rbx)
/* Actively align the La_x86_64_regs structure. */
andq $0xfffffffffffffff0, %rsp
# if defined HAVE_AVX_SUPPORT || defined HAVE_AVX512_ASM_SUPPORT
/* sizeof(La_x86_64_regs). Need extra space for 8 SSE registers
to detect if any xmm0-xmm7 registers are changed by audit
module. */
subq $(LR_SIZE + XMM_SIZE*8), %rsp
# else
subq $LR_SIZE, %rsp # sizeof(La_x86_64_regs)
# endif
movq %rsp, 24(%rbx)
/* Fill the La_x86_64_regs structure. */
movq %rdx, LR_RDX_OFFSET(%rsp)
movq %r8, LR_R8_OFFSET(%rsp)
movq %r9, LR_R9_OFFSET(%rsp)
movq %rcx, LR_RCX_OFFSET(%rsp)
movq %rsi, LR_RSI_OFFSET(%rsp)
movq %rdi, LR_RDI_OFFSET(%rsp)
movq %rbp, LR_RBP_OFFSET(%rsp)
leaq 48(%rbx), %rax
movq %rax, LR_RSP_OFFSET(%rsp)
/* We always store the XMM registers even if AVX is available.
This is to provide backward binary compatibility for existing
audit modules. */
movaps %xmm0, (LR_XMM_OFFSET)(%rsp)
movaps %xmm1, (LR_XMM_OFFSET + XMM_SIZE)(%rsp)
movaps %xmm2, (LR_XMM_OFFSET + XMM_SIZE*2)(%rsp)
movaps %xmm3, (LR_XMM_OFFSET + XMM_SIZE*3)(%rsp)
movaps %xmm4, (LR_XMM_OFFSET + XMM_SIZE*4)(%rsp)
movaps %xmm5, (LR_XMM_OFFSET + XMM_SIZE*5)(%rsp)
movaps %xmm6, (LR_XMM_OFFSET + XMM_SIZE*6)(%rsp)
movaps %xmm7, (LR_XMM_OFFSET + XMM_SIZE*7)(%rsp)
# ifndef __ILP32__
# ifdef HAVE_MPX_SUPPORT
bndmov %bnd0, (LR_BND_OFFSET)(%rsp) # Preserve bound
bndmov %bnd1, (LR_BND_OFFSET + BND_SIZE)(%rsp) # registers. Nops if
bndmov %bnd2, (LR_BND_OFFSET + BND_SIZE*2)(%rsp) # MPX not available
bndmov %bnd3, (LR_BND_OFFSET + BND_SIZE*3)(%rsp) # or disabled.
# else
.byte 0x66,0x0f,0x1b,0x84,0x24;.long (LR_BND_OFFSET)
.byte 0x66,0x0f,0x1b,0x8c,0x24;.long (LR_BND_OFFSET + BND_SIZE)
.byte 0x66,0x0f,0x1b,0x94,0x24;.long (LR_BND_OFFSET + BND_SIZE*2)
.byte 0x66,0x0f,0x1b,0x9c,0x24;.long (LR_BND_OFFSET + BND_SIZE*3)
# endif
# endif
# if defined HAVE_AVX_SUPPORT || defined HAVE_AVX512_ASM_SUPPORT
.data
L(have_avx):
.zero 4
.size L(have_avx), 4
.previous
cmpl $0, L(have_avx)(%rip)
jne L(defined)
movq %rbx, %r11 # Save rbx
movl $1, %eax
cpuid
movq %r11,%rbx # Restore rbx
xorl %eax, %eax
// AVX and XSAVE supported?
andl $((1 << 28) | (1 << 27)), %ecx
cmpl $((1 << 28) | (1 << 27)), %ecx
jne 10f
# ifdef HAVE_AVX512_ASM_SUPPORT
// AVX512 supported in processor?
movq %rbx, %r11 # Save rbx
xorl %ecx, %ecx
mov $0x7, %eax
cpuid
andl $(1 << 16), %ebx
# endif
xorl %ecx, %ecx
// Get XFEATURE_ENABLED_MASK
xgetbv
# ifdef HAVE_AVX512_ASM_SUPPORT
test %ebx, %ebx
movq %r11, %rbx # Restore rbx
je 20f
// Verify that XCR0[7:5] = '111b' and
// XCR0[2:1] = '11b' which means
// that zmm state is enabled
andl $0xe6, %eax
cmpl $0xe6, %eax
jne 20f
movl %eax, L(have_avx)(%rip)
L(avx512):
# define RESTORE_AVX
# define VMOV vmovdqu64
# define VEC(i) zmm##i
# define MORE_CODE
# include "dl-trampoline.h"
# undef VMOV
# undef VEC
# undef RESTORE_AVX
# endif
20: andl $0x6, %eax
10: subl $0x5, %eax
movl %eax, L(have_avx)(%rip)
cmpl $0, %eax
L(defined):
js L(no_avx)
# ifdef HAVE_AVX512_ASM_SUPPORT
cmpl $0xe6, L(have_avx)(%rip)
je L(avx512)
# endif
# define RESTORE_AVX
# define VMOV vmovdqu
# define VEC(i) ymm##i
# define MORE_CODE
# include "dl-trampoline.h"
.align 16
L(no_avx):
# endif
# undef RESTORE_AVX
# include "dl-trampoline.h"
cfi_endproc
.size _dl_runtime_profile, .-_dl_runtime_profile
#endif
#ifdef SHARED
.globl _dl_x86_64_save_sse
.type _dl_x86_64_save_sse, @function
.align 16
cfi_startproc
_dl_x86_64_save_sse:
# if defined HAVE_AVX_SUPPORT || defined HAVE_AVX512_ASM_SUPPORT
cmpl $0, L(have_avx)(%rip)
jne L(defined_5)
movq %rbx, %r11 # Save rbx
movl $1, %eax
cpuid
movq %r11,%rbx # Restore rbx
xorl %eax, %eax
// AVX and XSAVE supported?
andl $((1 << 28) | (1 << 27)), %ecx
cmpl $((1 << 28) | (1 << 27)), %ecx
jne 1f
# ifdef HAVE_AVX512_ASM_SUPPORT
// AVX512 supported in a processor?
movq %rbx, %r11 # Save rbx
xorl %ecx,%ecx
mov $0x7,%eax
cpuid
andl $(1 << 16), %ebx
# endif
xorl %ecx, %ecx
// Get XFEATURE_ENABLED_MASK
xgetbv
# ifdef HAVE_AVX512_ASM_SUPPORT
test %ebx, %ebx
movq %r11, %rbx # Restore rbx
je 2f
// Verify that XCR0[7:5] = '111b' and
// XCR0[2:1] = '11b' which means
// that zmm state is enabled
andl $0xe6, %eax
movl %eax, L(have_avx)(%rip)
cmpl $0xe6, %eax
je L(avx512_5)
# endif
2: andl $0x6, %eax
1: subl $0x5, %eax
movl %eax, L(have_avx)(%rip)
cmpl $0, %eax
L(defined_5):
js L(no_avx5)
# ifdef HAVE_AVX512_ASM_SUPPORT
cmpl $0xe6, L(have_avx)(%rip)
je L(avx512_5)
# endif
vmovdqa %ymm0, %fs:RTLD_SAVESPACE_SSE+0*YMM_SIZE
vmovdqa %ymm1, %fs:RTLD_SAVESPACE_SSE+1*YMM_SIZE
vmovdqa %ymm2, %fs:RTLD_SAVESPACE_SSE+2*YMM_SIZE
vmovdqa %ymm3, %fs:RTLD_SAVESPACE_SSE+3*YMM_SIZE
vmovdqa %ymm4, %fs:RTLD_SAVESPACE_SSE+4*YMM_SIZE
vmovdqa %ymm5, %fs:RTLD_SAVESPACE_SSE+5*YMM_SIZE
vmovdqa %ymm6, %fs:RTLD_SAVESPACE_SSE+6*YMM_SIZE
vmovdqa %ymm7, %fs:RTLD_SAVESPACE_SSE+7*YMM_SIZE
ret
# ifdef HAVE_AVX512_ASM_SUPPORT
L(avx512_5):
vmovdqu64 %zmm0, %fs:RTLD_SAVESPACE_SSE+0*ZMM_SIZE
vmovdqu64 %zmm1, %fs:RTLD_SAVESPACE_SSE+1*ZMM_SIZE
vmovdqu64 %zmm2, %fs:RTLD_SAVESPACE_SSE+2*ZMM_SIZE
vmovdqu64 %zmm3, %fs:RTLD_SAVESPACE_SSE+3*ZMM_SIZE
vmovdqu64 %zmm4, %fs:RTLD_SAVESPACE_SSE+4*ZMM_SIZE
vmovdqu64 %zmm5, %fs:RTLD_SAVESPACE_SSE+5*ZMM_SIZE
vmovdqu64 %zmm6, %fs:RTLD_SAVESPACE_SSE+6*ZMM_SIZE
vmovdqu64 %zmm7, %fs:RTLD_SAVESPACE_SSE+7*ZMM_SIZE
ret
# endif
L(no_avx5):
# endif
movdqa %xmm0, %fs:RTLD_SAVESPACE_SSE+0*XMM_SIZE
movdqa %xmm1, %fs:RTLD_SAVESPACE_SSE+1*XMM_SIZE
movdqa %xmm2, %fs:RTLD_SAVESPACE_SSE+2*XMM_SIZE
movdqa %xmm3, %fs:RTLD_SAVESPACE_SSE+3*XMM_SIZE
movdqa %xmm4, %fs:RTLD_SAVESPACE_SSE+4*XMM_SIZE
movdqa %xmm5, %fs:RTLD_SAVESPACE_SSE+5*XMM_SIZE
movdqa %xmm6, %fs:RTLD_SAVESPACE_SSE+6*XMM_SIZE
movdqa %xmm7, %fs:RTLD_SAVESPACE_SSE+7*XMM_SIZE
ret
cfi_endproc
.size _dl_x86_64_save_sse, .-_dl_x86_64_save_sse
.globl _dl_x86_64_restore_sse
.type _dl_x86_64_restore_sse, @function
.align 16
cfi_startproc
_dl_x86_64_restore_sse:
# if defined HAVE_AVX_SUPPORT || defined HAVE_AVX512_ASM_SUPPORT
cmpl $0, L(have_avx)(%rip)
js L(no_avx6)
# ifdef HAVE_AVX512_ASM_SUPPORT
cmpl $0xe6, L(have_avx)(%rip)
je L(avx512_6)
# endif
vmovdqa %fs:RTLD_SAVESPACE_SSE+0*YMM_SIZE, %ymm0
vmovdqa %fs:RTLD_SAVESPACE_SSE+1*YMM_SIZE, %ymm1
vmovdqa %fs:RTLD_SAVESPACE_SSE+2*YMM_SIZE, %ymm2
vmovdqa %fs:RTLD_SAVESPACE_SSE+3*YMM_SIZE, %ymm3
vmovdqa %fs:RTLD_SAVESPACE_SSE+4*YMM_SIZE, %ymm4
vmovdqa %fs:RTLD_SAVESPACE_SSE+5*YMM_SIZE, %ymm5
vmovdqa %fs:RTLD_SAVESPACE_SSE+6*YMM_SIZE, %ymm6
vmovdqa %fs:RTLD_SAVESPACE_SSE+7*YMM_SIZE, %ymm7
ret
# ifdef HAVE_AVX512_ASM_SUPPORT
L(avx512_6):
vmovdqu64 %fs:RTLD_SAVESPACE_SSE+0*ZMM_SIZE, %zmm0
vmovdqu64 %fs:RTLD_SAVESPACE_SSE+1*ZMM_SIZE, %zmm1
vmovdqu64 %fs:RTLD_SAVESPACE_SSE+2*ZMM_SIZE, %zmm2
vmovdqu64 %fs:RTLD_SAVESPACE_SSE+3*ZMM_SIZE, %zmm3
vmovdqu64 %fs:RTLD_SAVESPACE_SSE+4*ZMM_SIZE, %zmm4
vmovdqu64 %fs:RTLD_SAVESPACE_SSE+5*ZMM_SIZE, %zmm5
vmovdqu64 %fs:RTLD_SAVESPACE_SSE+6*ZMM_SIZE, %zmm6
vmovdqu64 %fs:RTLD_SAVESPACE_SSE+7*ZMM_SIZE, %zmm7
ret
# endif
L(no_avx6):
# endif
movdqa %fs:RTLD_SAVESPACE_SSE+0*XMM_SIZE, %xmm0
movdqa %fs:RTLD_SAVESPACE_SSE+1*XMM_SIZE, %xmm1
movdqa %fs:RTLD_SAVESPACE_SSE+2*XMM_SIZE, %xmm2
movdqa %fs:RTLD_SAVESPACE_SSE+3*XMM_SIZE, %xmm3
movdqa %fs:RTLD_SAVESPACE_SSE+4*XMM_SIZE, %xmm4
movdqa %fs:RTLD_SAVESPACE_SSE+5*XMM_SIZE, %xmm5
movdqa %fs:RTLD_SAVESPACE_SSE+6*XMM_SIZE, %xmm6
movdqa %fs:RTLD_SAVESPACE_SSE+7*XMM_SIZE, %xmm7
ret
cfi_endproc
.size _dl_x86_64_restore_sse, .-_dl_x86_64_restore_sse
#endif